[52.03] Cosmological Enrichment and Entropy Production by Galactic Winds

W. G. Mathews (University of California, Santa Cruz)

Galactic winds are thought to have influenced both the metal
enrichment and entropy of hot gas in galaxy clusters. The
nearly solar metal abundance in the hot gas in rich clusters
of galaxies can result from supernova-driven galactic winds
during the early starburst evolution of galactic bulges.
Similarly, the entropy of the hot gas in galaxy groups,
which exceeds that acquired in accretion shocks, is a relic
of the same supernova heating during early star formation.
The number of early Type II supernovae required to account
for the observed Lx - temperature and entropy - T
correlations suggests an initial mass function that is
somewhat flatter than Salpeter. At the present time the hot
gas in most massive large elliptical galaxies is flowing
inward as a cooling flow, although winds are possible in
ellipticals of moderate or small mass.